Recently Audio Kinetic published a blog by Tom Todia discussing using images to automate parameters in Wwise to help create the audio for the waves in an open world shark game. You can read it here: http://blog.audiokinetic.com/open-world-ambient-design-using-image-based-parameters 

Extending the feature further with multiple images could allow me to automate multiple parameters. With that I could then have a base layer of ambiences controlled completely by one 2D emitter.

The idea in FMOD would look something similar to this:

And it would be activated by a raycast from the player, going to the image directly below the map. (credit audiokinetic)

Using separate parameters, the raycast could ignore images for the other parameters to read only a single specific image. Eg. there will be an image for forrest, an image for static water and an image to moving water.

While this would definitely not replace 100% off environmental audio in the game, but on large maps, with awkward environment shapes like rivers, this could save a lot of time.

I’m hoping to get this running in game soon to see how effective it will be.